Tunnel liner



July 13, 1943. l G O M 2,323,906

' TUNNEL LINERS Filed Oct. 2, 1939 5 Sheets-Sheet l INVENTOR.

GEORGE O.HARM.

ATTORNEYS.

July 13, 1943'. a Q HARM 2,323,906

TUNNEL LINERS Filed 001;. 2, 19.39 s Sheets-Sheet 2 INVENTOR. GEORGE IO.HARM

" I fQW ATTORNEYS.

July 13, 1943. Q 0 HARM 2,323,906

TUNNEL LINERS Filed Odt. 2, 1939 a Sheets-Sheet 5 IIEJZ.

} INVENTOR. GEORGE 0. HARM TT'O Patented July 13, 1943 TUNNEL LINER George 0. Harm, Warren, Ohio, assignor to .The

Johnston & Jennings Company, Cleveland; Ohio, a corporation of Ohio Application October 2, 1939, Serial No. 297,517

4 Claims.

The present invention relates to a new and improved construction for a tunnel liner. In tunneling operations, the function of primary lining is to present'a continuous surface to the exposed earth and to resist the pressures of the earth. Present methods of liner construction separate these two functions inasmuch as steel plates or pans are used to make continuous contact with the earth, the pressure on these pans being transferred to ribs designed to carry the total imposed load. In some cases the total imposed load is carried by placing plates or pans in staggered relationship with the result that alternate courses of pans act as ribs spliced by adjacent pans placed in staggered relation. Both of the aforementioned methods have a low load supporting value in proportion to the amount of steel used. I

It is the general object and nature of my invention, therefore, to provide a novel, efiicient and economical construction of tunnel liner, and especially of the units which are assembled to form such liner wherein the two aforementioned functions are accomplished in an essentially unit structure, and substantially all of the steel employed in such structure acts directly to support the total imposed load. That is to say, the material in the load-carrying members is so disposed that it also functions as a facing material.

The structure embodying the principle of my invention is also well adapted to be used with a cutting edge or tunneling shield. Where such a tunneling shield is employed, the tunnel liner must serve a function in addition to those mentioned above, viz: it must be capable of withstanding a. force directed in a horizontal direction and caused by the forward driving force exerted upon the shield. It is an additional object of my invention to provide a structure which will be capable of safely withstanding the exertion of these above-enumerated forces, and wherein such forces will be uniformly, to maximum advantage, distributed throughout the component parts of the liner.

Additional objects and advantages of my invention include the provision of means for sealing the joints between the units against loss of air pressure or entrance of water, and means larities which might interfere with the assembly of the liner within the excavation or within the tunneling shield, and incidentally with the forward progress of the latter.

Also, since the structure embodying my invention presents a tunnel lining in which the last, or most advanced course of units is just as strong as the intermediate courses, a substantial reduction in the length of the tail of the tunneling shield is rendered possible, since such tail need not be otherwise extended in length inorder to obtain sufiicient support over a plurality of courses of uneven strength.

A further object of the invention is to provide a construction which may be made up of a plurality of units which may be assembled in the field with a minimum amount of labor and with a substantially reduced amount of separate parts, such as nuts and bolts, brackets, angle irons, rods, beams, etc.

The tunnel liner constructed according to the principles of my invention also possesses the advantage in that one or more panel units may be conveniently removed after assembly, where it is desired to insert a cross-connection, or in the case of the adjoining twin tunnels, for example. Additional objects and advantages of my invention shall become apparent as the following description proceeds:

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims. The annexed drawings and the following description set forth in detail certain structure embodying the inventionQsuch disclosed means constituting, however, but one of various structural forms in which the principle of the invention may be used.

In said annexed drawings:

Fig. 1 is a longitudinally broken sectional View of the assembled tunnel liner and shield embodying my invention; Fig. 2 is a transverse view of the tunnel liner; Fig. 3 is a perspective view of one of the panel units; Fig. 4 is an enlarged detailed view of the joint between two adjacent panel units; Fig. 5 is an enlarged, fragmentary,

longitudinal sectional view of the liner; Fig. 6

is an enlarged, detailed sectional view showing the interlocking fastening means between the ends of the reinforcing ribs of the panel units; Fig. 7 is an enlarged detailed sectional view of the curved edge assembly and joint of adjacent panel units; Fig. 8- is a'detailed view showing the use of a shim between the ends of the longitudinal compression members for the purpose of accommodating a curvature or deviation in the line of the tunnel; Fig. 9 is a detailed view showing a modified form of interlocking means between the ends of the reinforcing ribs; Fig. 10 is a view taken upon a plane normal to that of Fig. 9; Fig. 11 is a sectional view taken substantially along line IIII of Fig. 12, and illustrating an alternative form of construction of the reinforcing members; and Fig. 12 is a view taken upon a plane normal to that of Fig. 11.

Now referring more particularly to the drawings, Fig. 1 thereof shows the assembled tunnel liner, indicated generally by the numeral I, with the shield 2 mounted in position for forward progress, viz., in a right-hand direction with respect to Fig. 1, and with the screw-jacks 3 mounted between the shield 2 and the most advanced panel units, or the forward course, of the liner I.

As will be immediately appreciated from the foregoing reference to Fig. 1, it will be seen that the tunnel liner is composed of a plurality of panel units 5 Whose detailed construction is shown in Figs. 3 to '7 inclusive. The panel unit 5 is composed of a longitudinally curved plate having the inwardly ofiset marginal portions 6 and I along each of its curved outer edges.

Referring particularly to Fig. 7, it will be seen that the offset margin 6 is offset to a greater distance inwardly than the margin I. This distance is substantially equal, of course, to the thickness of the plate of the panel 5, so that the margins 6 and I of the individual panel units can be assembled in overlapping or telescoping relationship.

The margins 6 and I also have drilled holes 8 and 9 respectively, which are so located as to be in alignment when the panel units 5 are assembled with their offset marginal portions overlapping, as above described. The marginal portions 1 of each of the panel units carries a nut III whose internal threads are in alignment with the holes 8 and 9. The nut I is fixed to the margin I in such properly aligned position by means of a tack weld, such as indicated at II. The nuts III are adapted to receive the bolts I2 inserted from the inner face of the tunnel liner or panel units 5. The margin 1 is inwardly offset from the outer face of the panel a distance slightly greater than the thickness of the nut I0, so that there will be no projecting part beyond such outer surface when the units are assembled.

Reinforcing ribs in the form of longitudinally curved I-beams I3 and I4 are mounted upon the inner face of the panel 5. The ribs I3 and I4 may be satisfactorily secured in position on the panel 5 by means of Welding a flange thereto. Longitudinally interlocking means comprising the toothed fish plates I 5, I6, I1 and I8, are located on each end of the ribs I3 and' I4, being Welded to the web thereof. As will best be seen by reference to Fig. 6, the locking plates I5, I6, I1 and I8 have intermeshing teeth I9, which teeth, when drawn together by the bolts 20, positively lock the adjacent ribs I3 and I4 and their corresponding panel units 5 against longitudinal movement. It will be noted, by reference to Fig. 3, that the plates I5 and I6, on one end of the ribs I3 and I4, are so positioned as to have their teeth I9 facing in opposite direction to the teeth on the plates I! and I8 on the other end of the ribs I3 and I4. Thus, any one panel unit 5 can be properly fitted and interlocked with any other adjacent panel unit and so on around the circumference of the liner. Recesses 2| are located in the outer faces of the plates I5 to I8 and are for the purpose of receiving the heads or nuts of the fastening bolts 20.

Compression members in the form of round bars 22 are mounted transversely of the ribs I3 and I4. The bars 22 are secured in such position by being welded around their circumference to the webs of the ribs I3 and I4. The plain ends 23 of the bars 22 extend, as will be seen from Figs. 4 and 5, at least as far as the edge of the marginal portion I of the panel 5, and are adapted to be received within the socket 24 on the opposite end of the bar 22 of the next adjacent panel unit. The socket 24 is made to have a loose fit with the plain end 23 and the clearance space therebetween is filled with a packing material, as indicated at 25.

Marginal opening 26 are provided in the offset margins 6 at points adjacent the socketed ends 24 of the bars 22 and are for the purpose of clearing the plain ends 23 of such bars during assembly of the panel units 5.

Directing attention particularly to Fig. 5, the bars 22, where the removable panel units 5 are to be installed, are made without socketed ends 24 and are slightly shorter than the bars in nonremovable units, the required length of the bars being made up by inserting loose piece 22. A

semi-cylindrical retaining member or half shell 2'! is welded to this shorter section 22' so that both ends of the shell extend beyond the ends. This shell laps the abutting ends of adjacent bars and holds the shorter piece against lateral displacement. In removal of the panel member 5 the sectional piece 22 is moved upwardly out of place, bolts I2 and 20 are removed and the panel unit is slid in a lefthand direction (with respect to Fig. 5), then lifted out of place. Another change from previously described construction of Fig. 3, which is necessary in this case, is that the locking plates at the ends of the ribs are so disposed that the interlocking teeth in the first panel to be removed from a ring will unmesh in the same direction.

Such a removal of panel units is often desirable as in the case of a twin or common-wall tunnel, in which units 5a and 5b shown in Fig. 2, for example, are to be removed after the adjacent tunnel is cut. Location of the adjacent tunnel is represented in Fig. 2 by the presence of the panel unit 50, connected to the unremoved panel unit 5:2 in a suitable manner as by the angle beam 21'.

Where the tunnel undergoes a change or curvature in horizontal line or grade, the resulting required differences in length of the bars 22 is accommodated by means of the insertion of shims 29, such as indicated in Fig. 8. Thus, in a vertical section taken through a longitudinally curved portion of the tunnel, those compression bars 22 located on the line of a shorter radius of curvature will abut directly against each other, while those on greater radii of curvature will be correspondingly spaced further apart from each other, and such spaces are taken up by the shims 29.

A grout hose connection 28 is located on the inner face of the panel 5 for introducing filling and sealing material around the outer face of the liner and between it and the surrounding earth.

The reinforcing ribs I3 and I4 are preferably spaced inwardly from the margins 6 and I at a distance approximately equal to one-quarter of the Width of the panel unit 5, so that on assembly of such panel units, the reinforcing ribs I 3 and I4 will be equidistantly spaced throughout the length of the tunnel liner. This latter relationship is clearly illustrated in Figs. 1 and 5. Such relationship insures a uniform and safe distribution of the longitudinal force exerted upon ends of the bars 22 by means of the screw-jacks 3 and also of the earth pressure exerted radially against the outer surface of the tunnel liner. Th compressive force exerted upon the bars 22 is transmitted primarily through the ribs [3 and M to the intermediate, rather than the marginal portions of the panel units 5, thus reducing the amount of strain which would otherwise be exerted upon the lateral or curved edge joints between such units. By the same token, the panel units 5, in effect, become flanges of the ribs l3 and I4, throughout the length of the liner, and this results in a combined stress-resisting structure, effective throughout the outer surface of the tunnel liner against the earth pressure. This not only obviates the necessity of additional shoring or bracing members, but also eliminates any points in such surface which are likely to be unevenly braced, and hence, subjected to unequal bending stresses. The teeth l9 also brace the ribs l3 and Hiagainst movement of the ribs in a radially inward or outward direction of the assembled tunnel liner, thus insuring circumferential rigidity of the assembled reinforcing ribs and the panel units 5 carried upon them.

An alternative form of interlocking means between the ends of the reinforcing ribs is shown in Figs. 9 and 10. Thus, plates 33 welded to each end of the ribs l3 are adapted to over-lap each other when the panel units 5 are assembled.

Tapered pins 31 extend through tapered, aligned holes in the plates 30, and are adapted to be drawn tightly into position by means of the nuts 33 engaging their threaded end 32.

An alternative form of construction for the reinforcing rib members is shown in Figs. 11 and 12. In this latter form of construction, the reinforcing ribs are in the form of single channels rather than that of dual I-beams. The panel units 5, of course, are essentially identical in construction with those previously described.

Another method of construction would be to press the channel from the material forming the panel and welding a plate across the bottom of the channel thus formed, thereby making a tube. The ends of the channel 35 are interlocked in assembly by means of a saddle 31 through which the bolts 38 pass and engage the nuts 42 which are tack welded to the backs of the panels. The saddles 31 are carried at one end of the panel units 5 and are permanently attached thereto, such as by means of the weld indicated at 39. Holes 36 are located in the face of the panel unit 5' and a grout hose connection 40 is located in the channel 35 in at least one unit of each ring of units. When the units 5' are assembled as described, the connected channels form a continuous tube around the perimeter of the tunnel. As soon as erected, this tube is filled with grout material 41 by means of the inlet 40 and the grout passes through the holes 36 into cavities between the liner and the earth until all such cavities and. the tube itself are filled. As the concret in the tube hardens, it adds greatly to the strength of the tubular rib.

It should be noted that it is not necessary to use a plurality of reinforcing ribs in order to obtain the primary results of this invention, in fact, a single rib in the center of a narrower panel is preferable where the units are to be handled manually. Connections and essential elements would be the same as described herein.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made 'as regards the structure herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. A tunnel liner unit comprising a curved panel member, the marginal curved edge portions of said panel member being inwardly offset from the outer surface thereof, one of said marginal portion being offset a greater distance inwardly than the other, such distance being substantially equal to the thickness of said panel member.

2. A tunnel liner unit comprising a curved panel member, the marginal curved edge portions of said panel member being inwardly oifset from the outer surface thereof, one of said marginal portions being offset a greater distance inwardly than the other, such distance being substantially equal to the thickness of said panel member, bolt holes in said marginal portions located to be in alignment with similar bolt holes in another unit on assembly of the same, and nuts fixed to the outer surface of said other of said marginal portions and in alignment with said bolt holes.

3. A tunnel liner unit comprising a curved panel member, the marginal curved edge portions of said panel member being inwardly offset from the outer surface thereof, one of said marginal Dortions being offset a greater distance inwardly than the other, such distance being substantially equal to the thickness of said panel member, bolt holes in said marginal portions located to be in alignment with similar bolt holes in another unit on assembly of the same, and nuts fixed to the outer surface of said other of said marginal portions and in alignment with said bolt holes, the amount of offset of said other of said marginal portions being at least equal to the thickness of said nuts.

4. In a device of the character described, a curved tunnel liner section comprising a plurality of units for arrangement end to end with respect to each other, each of said units comprising a substantially smooth panel facing member having a curvature conforming to the contour of said section, and a reinforcing rib, formed separately from but rigidly secured to the inner surface of said panel member, and means for securing the ends of said ribs together to position said panel members in end to end relation and to form a support for the same comprising intermeshed tooth-shaped elements provided on the ends of said ribs for interlocking adjacent ribs and the panels secured thereto against movement with respect to each other.

GEORGE O. HARM. 

